The big day arrives and Nick Griffin, leader of the racist BNP, finally prepares to take his seat on Question Time – only to find there have been some changes. David Dimbleby has swine flu; instead, host for the evening will be Sir Trevor MacDonald. Diane Abbott, Jesse Jackson, Linda Bellos and the comedian Shazia Mirza are the other panellists. The venue has changed, too; unavoidable, a regrettable case of double booking. Still, all will go well in Handsworth, he is told. The alternative was Peckham.

This is all fantasy, alas, for Dimbleby is in rude health, and the chances are that quite a few of our would-be panellists wouldn't hose Griffin down if he was on fire, much less appear alongside Britain's most high-profile extremist. But what is not fantasy is that Griffin will appear on Question Time sometime soon, and as he prepares to parade his bigotry to the nation on prime time, it might be a good moment to reflect on a few hard facts about the country he now represents in Brussels.

Eighty-five per cent of the inhabitants of our country describe themselves as white British. The largest visible minority group is of Indian origin, comprising just 2% of the population. And forget headlines to the contrary; about half of us are optimistic that Britain will be a more tolerant society in 10 years' time, and 70% would be comfortable – in theory – to see their children choose a partner of a different race or faith. And that's just as well, for many of them already have. Nine per cent of our children live in homes with multiple heritages: 9% and rising. People voting with their squashy bits. The dreaded miscegenation, Mr Griffin. Horizontal integration.

The facts do not suggest that indigenous white Britain feels besieged by different races. In fact, for the most part, "native" Britons, as Griffin likes to call those deemed acceptable, handle the juxtaposition of people with different skin colours comparatively well. Certainly better than many countries on mainland Europe: just ask many black British families about their experiences on trips to places such as Italy, Germany and parts of France.

Even the BNP, in its public pronouncements, recognises this. Oh, they don't like the darkies and never will, but the sell to the public has, through necessity, been repackaged. It's not the darkies per se, it's the crime they bring with them. It's not the Muslims because of who they are – yeah, right? – it's what they do. It's not that we're afraid of difference, but these Poles, half of them don't even speak proper English. And they work too cheaply.

The frontline was once marked out by race, but these days it zigzags: it's race, it's culture, it's working space, it's living space. It's how much immigrants have brought with them; how much they have left behind. How much they are willing to compromise; how much others in society think they should.

How well Britain deals with diversity is not so much about a yearning for homogeneity. Instead, the drama we see being played out daily is about the rules of engagement. That makes it sound bloodless; it's anything but. The rules of engagement will govern whether parents, be they Jewish, Muslim or Catholic, are allowed to separate their children in their own schools. Whether they want to. Whether anxieties are eased about the burka. Whether they ought to be. Whether, or when, we all speak English. It's bare-knuckle stuff. It raises hackles. It's all sensitive.

Our society may not always work as we would like it to, but it does kind of work, even as we read about the rows and conflicts, magnified through the crooked lenses of some newspapers. Even as we laugh at Carol Thatcher trying to explain that she didn't know it was non-U to describe a black man as a golliwog. Even when a councillor in Barnet blacks up for a fancy dress party as Nelson Mandela and professes surprise when people object. Even when white far-righters and football hooligans, self-cast as warriors against "Islamic extremism", clash with Asian youths in Birmingham. Even when, as occurred this week, commentators despair because so many babies born last year were called Mohammed.

The interaction between the various and varied elements of our 21st-century society causes worry, confusion, sometimes discord, sometimes bloodshed – but isn't that inevitable? It is fascinating, but it shouldn't be justification for doom and gloom. It's just the way we rub along, progressing step by uncertain step.